In the class diagram, it is represented by string type.
在类关系图中，它由string type加以表示。
2
Diagram 17 shows a triangle constructed using a piece of string.
图17显示以一条绳子所制造成的一个三角形。
3
Under a given condition, strength expressions of rod string is discussed and a linear diagram is derived which can be used to check the strength of rod string.